Source of Emissions
The combustion process produces carbon monoxide, oxides of nitrogen, and hydrocarbons.
Control of hydrocarbons and oxides of nitrogen is very important because, under certain
conditions, they react to form photochemical smog when subjected to sunlight. Carbon
monoxide does not react in the same way, but it is toxic.
This utilizes lean carburetor settings and other systems to reduce the emissions of
carbon monoxide, oxides of nitrogen and hydrocarbons.
Tampering and Altering
Tampering with or altering the emission control system may increase emissions beyond
the legal limit. Among those acts that constitute tampering are:
Removal or alteration of any part of the intake, fuel or exhaust systems.
Altering or defeating the governor linkage or speed-adjusting mechanism to cause
the engine to operate outside its design parameters.
Problems That May Affect Emissions
If you are aware of any of the following symptoms, have your engine inspected and
repaired by your servicing dealer.
Hard starting or stalling after starting.
Rough idle.
Misfiring or backfiring under load.
Afterburning (backfiring).
Black exhaust smoke or high fuel consumption.
Replacement Parts
The emission control systems on your engine were designed, built. We recommend the
use of genuine parts whenever you have maintenance done. These original-design
replacement parts are manufactured to the same standards as the original parts, so you
can be confident of their performance. The use of replacement parts that are not of the
original design and quality may impair the effectiveness of your emission control system.
A manufacturer of an after market part assumes the responsibility that the part will not
adversely affect emission performance. The manufacturer or rebuilder of the part must
certify that use of the part will not result in a failure of the engine to comply with
emission regulations.
Maintenance
Follow the maintenance schedule. Remember that this schedule is based on the
assumption that your machine will be used for its designed purpose. Sustained high-load
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TECHNICAL & CONSUMER INFORMATION
